Task 'pop3 - Receiving' reported error (0x80040900) in MS Office

Task 'pop3 - Receiving' reported error (0x80040900) : 'The server name you
entered can not be found on the network (it might be down temporarily).
Please verify that you are online and that the server name is correct.'

I am getting this error message when i am clicking on send/receive button to
get my mails. while sending mails i am not finding any problem but when i
wants my mails to be downloaded then i am getting this error message. any
quick solution will be apprieciated.